I start with really easy, simple behaviors. Once they learn one or two of those they begin to understand that offering behavior is what it's all about. Puppies get really creative with offering once they know the rules of the game and you can get some crazy things to build off of.
My first behaviors to teach are object interaction based. Here's a box, what can you do with this box? Click for whatever they offer first and continue to click for it until they are offering it readily. Next time, use a different object and try to click for something else until it's offered readily. So on so forth. Targets are great for this, I teach a hand target right away.
You can shape ANY behavior out there, don't fall into the trap that because it's X behavior you must lure it. You just need to have a good understanding of how to build on offered behaviors and a dog who knows the game. For example, I have free shaped a down and a head toss which eventually turned into a rollover. That same head toss turned into a spin and also a sit up and beg. Be creative with those quirky offered things, you can build a ton on them!